<SEC-DOCUMENT>0001104659-19-002515-index.html : 20190118
<SEC-HEADER>0001104659-19-002515.hdr.sgml : 20190118
<ACCEPTANCE-DATETIME>20190118170255
ACCESSION NUMBER:		0001104659-19-002515
CONFORMED SUBMISSION TYPE:	DEFA14A
PUBLIC DOCUMENT COUNT:		2
FILED AS OF DATE:		20190118
DATE AS OF CHANGE:		20190118
EFFECTIVENESS DATE:		20190118

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			TETRA TECH INC
		CENTRAL INDEX KEY:			0000831641
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-ENGINEERING SERVICES [8711]
		IRS NUMBER:				954148514
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0930

	FILING VALUES:
		FORM TYPE:		DEFA14A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-19655
		FILM NUMBER:		19533734

	BUSINESS ADDRESS:	
		STREET 1:		3475 EAST FOOTHILL BOULEVARD
		CITY:			PASADENA
		STATE:			CA
		ZIP:			91107
		BUSINESS PHONE:		6263514664

	MAIL ADDRESS:	
		STREET 1:		3475 EAST FOOTHILL BOULEVARD
		CITY:			PASADENA
		STATE:			CA
		ZIP:			91107
</SEC-HEADER>
<DOCUMENT>
<TYPE>DEFA14A
<SEQUENCE>1
<FILENAME>a19-2979_3defa14a.htm
<DESCRIPTION>DEFA14A
<TEXT>
Document 1 - file: a19-2979_3defa14a.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>2
<FILENAME>g29793bii001.gif
<DESCRIPTION>GRAPHIC
<TEXT>
Document 2 - file: g29793bii001.gif

</DOCUMENT>
</SEC-DOCUMENT>